US20020003314A1 - Aeration device for water and a method for manufacturing an aeration device - Google Patents

Aeration device for water and a method for manufacturing an aeration device Download PDF

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Publication number
US20020003314A1
US20020003314A1 US09/261,493 US26149399A US2002003314A1 US 20020003314 A1 US20020003314 A1 US 20020003314A1 US 26149399 A US26149399 A US 26149399A US 2002003314 A1 US2002003314 A1 US 2002003314A1
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US
United States
Prior art keywords
aeration device
carrier
membrane
aeration
air
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US09/261,493
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English (en)
Inventor
Thomas Cantz
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huber and Suhner AG
Original Assignee
Huber and Suhner AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huber and Suhner AG filed Critical Huber and Suhner AG
Assigned to HUBER + SUHNER AG reassignment HUBER + SUHNER AG ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CANTZ, THOMAS
Publication of US20020003314A1 publication Critical patent/US20020003314A1/en
Abandoned legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/02—Aerobic processes
    • C02F3/12—Activated sludge processes
    • C02F3/20—Activated sludge processes using diffusers
    • C02F3/201—Perforated, resilient plastic diffusers, e.g. membranes, sheets, foils, tubes, hoses
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/231—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids by bubbling
    • B01F23/23105—Arrangement or manipulation of the gas bubbling devices
    • B01F23/2311—Mounting the bubbling devices or the diffusers
    • B01F23/23115—Mounting the bubbling devices or the diffusers characterised by the way in which the bubbling devices are mounted within the receptacle
    • B01F23/231151—Mounting the bubbling devices or the diffusers characterised by the way in which the bubbling devices are mounted within the receptacle the bubbling devices being fixed or anchored in the bottom
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/231—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids by bubbling
    • B01F23/23105—Arrangement or manipulation of the gas bubbling devices
    • B01F23/2312—Diffusers
    • B01F23/23124—Diffusers consisting of flexible porous or perforated material, e.g. fabric
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/231—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids by bubbling
    • B01F23/23105—Arrangement or manipulation of the gas bubbling devices
    • B01F23/2312—Diffusers
    • B01F23/23125—Diffusers characterised by the way in which they are assembled or mounted; Fabricating the parts of the diffusers
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F7/00—Aeration of stretches of water
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/20—Mixing gases with liquids
    • B01F23/23—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids
    • B01F23/231—Mixing gases with liquids by introducing gases into liquid media, e.g. for producing aerated liquids by bubbling
    • B01F23/23105—Arrangement or manipulation of the gas bubbling devices
    • B01F23/2312—Diffusers
    • B01F23/23126—Diffusers characterised by the shape of the diffuser element
    • B01F23/231264—Diffusers characterised by the shape of the diffuser element being in the form of plates, flat beams, flat membranes or films
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Definitions

  • the invention relates to an aeration device for water, in particular for waste water and to a method for manufacturing an aeration device.
  • tubular aerators are applied which are surrounded by a membrane through which small air bubbles may exit into the water to be aerated.
  • Such tube aerators are often described as line aerators because the aerators may be arranged in a line in the clearing basin.
  • aeration plates consist generally of a round support plate, through which air is supplied, and of a porous membrane fastened to the edge of the support plate.
  • Such plate aerators are placed individually onto an air supply conduit layed in the clearing basin.
  • Plate aerators are complicated in their manufacture and in particular in their assembly.
  • a further object of the present invention lies in providing a simple method for manufacturing such an aeration device.
  • the invention may also be applied to the aeration of still water, such as natural ponds or breeding ponds.
  • the aeration device consists essentially of a carrier with a flat or arcuate, essentially rectangular-shaped surface with longitudinal and transverse sides.
  • the ratio of the length to width of at least 3, preferably at least 15:1 permits the optimal, rational manufacture as extrusion parts.
  • the rectangular surface ensure a homogeneous exit of the small gas bubbles and also permits modular components with a variable length to be manufactured. Different from plate aerators, with an aeration device according to the present invention a freely selectable length in a clearing basin may be equipped with a single aeration device.
  • the ratio of the length of the longitudinal and transverse sides is about 15 to 1 to 30 to 1.
  • an air permeable membrane which preferably at least partly, along the longitudinal sides of the surface, is connected to the carrier.
  • the membrane and carrier enclose at least one air chamber.
  • An air supply arrangement for filling the air chamber with air is provided. As soon as air under pressure is introduced into the air chambers the membrane curves, the pores of the membrane open and the air may exit into the waste water to be aerated.
  • Such an aeration device may preferably be manufactured by coextrusion of a carrier and of a membrane.
  • the carrier consists generally of a relatively rigid material and the membrane must have a sufficient strength and elasticity.
  • the carrier and the membrane may be manufactured and simultaneously permanently connected to one another.
  • a coextrusion method may also be applied to aeration devices which comprise a carrier with a non-flat surface.
  • the simplicity of the manufacturing method in this case also comes to fruition.
  • the membrane along a middle line running essentially parallel to the longitudinal sides of the surface of the carrier, is connected to the surface of the carrier.
  • the membrane and the carrier enclose two air chambers.
  • the distribution of the small gas bubbles is improved since the curvature of the surface of the individual air chambers becomes smaller.
  • the air chambers of the aeration device are connectable along at least one transverse side to the air supply means.
  • connection to an air supply on the transverse side simplifies the construction of the carrier, since in contrast to plate aerators no air supply in the carrier itself is necessary. Thus a coextrusion method can be carried out particularly simply.
  • the carrier is provided with fastening means for the releasable and positive and non-positive fitting connection of the aeration device in a retaining device.
  • the releasable and positive and non-positive connection of the aeration device in the retaining device has advantageous effects in particular for the maintenance, i.e. for the exchange of the aeration devices. Thanks to the releasable connection, the aeration device may be simply lifted from the retaining device and removed from the clearing basin, without the clearing basin having to be emptied. Of course such a releasable connection is also advantageous with other types of aeration devices.
  • the fastening means are arranged on the lower side distant to the surface of the carrier.
  • the aeration device may further comprise cavities which may be filled out with a ballasting medium.
  • the cavities between the carrier and membrane of the aeration device and in the air supply produce a thrust which normally requires a firm anchoring of the aeration device. On account of the cavities for receiving a ballasting material this thrust may be essentially compensated. The necessity of a stable anchoring is therefore done away with. Since no stable anchoring is required the releasability of the aeration device from the retaining device is particularly simple in accomplishing.
  • the cavities are mounted in the fastening means of the aeration device.
  • the fastening means may in particular be formed as an essentially cylindrical tube which along a circumferential section may be snapped into a retaining device and which is formed for receiving a ballasting medium.
  • An aeration device with a flat carrier and fastening means with an essentially round cross section may be extruded particularly simply.
  • the aeration device is furthermore provided with means for draining the air chambers. It is possible that during operational interruptions water may enter into the air chambers. It is therefore advantageous when the draining means function automatically, i.e. possibly contained water is immediately ejected from the air chambers.
  • the carrier may be manufactured of polypropylene and the membrane from a thermoplastic elastomer. By way of coextrusion these two materials may be connected to one another and the mechanical properties different for the carrier and the membrane are ensured.
  • the aeration device is advantageously manufactured by coextrusion. With this a carrier and the membrane are commonly extruded in each case of an individual raw material and connected to one another by the extrusion.
  • the membrane subsequently is subjected to a method for increasing its air permeability, in particular to perforation.
  • the coextrusion method is of interest in particular with regard to modular components.
  • the advantage of modular components may however be achieved also very generally with aeration devices which consist of an extruded plastic hollow profile.
  • the ratio of height to width should in this case be at least 1:3. It is the case here therefore of a relatively narrow aerator.
  • the profile may consist of a single material which is perforated for producing a gaspermeable surface. In such a case at least one middle web in the cavity is for increasing the stability. It is however also conceivable to manufacture such a profile from two materials which have a differing mechanical strength (rigid lower part/flexible upper part).
  • FIG. 1 a schematic perspective representation of an aeration device according to the invention
  • FIG. 2 a schematic representation of an alternative embodiment example in cross section
  • FIG. 3 a cross section through an aeration device according to the invention
  • FIG. 4 a schematic representation of an aeration device according to the invention, in a retaining device
  • FIG. 5 a schematic representation of an aeration device according to the invention, with an air supply
  • FIG. 6 a schematic representation of means for draining the air chambers.
  • FIG. 1 there is schematically shown an aeration device 1 according to the invention.
  • the aeration device 1 consists essentially of a carrier 2 with a flat surface 3 and with longitudinal sides 4 and transverse sides 5 .
  • a membrane 6 is connected to the carrier.
  • the membrane 6 and the carrier 2 enclose an air chamber 7 a .
  • the membrane 6 may likewise be connected directly to the carrier 2 along the transverse side 5 or special connection pieces may be used.
  • On the one side the air chamber 7 a is closed along the transverse side 5 and on the other side there is provided an air connection 10 , which via a connection conduit 12 is connected to an air conduit.
  • the membrane 6 is provided with perforations which permit the exit of small air bubbles into the waste water to be cleared.
  • aeration devices 1 In a clearing basin there are arranged several aeration devices 1 .
  • the aeration devices 1 are designed in a modular construction in modules of various lengths. This construction permits an individual equipping of the clearing basin with aeration devices 1 .
  • the aeration devices 1 are releasably held in each case on two retaining devices 16 with a positive and non-positive fit, which permits an easy assembly and removal of the aeration device 1 .
  • Each of the aeration devices 1 is connected to an air conduit via a flexible air supply tubing 12 .
  • FIG. 2 shows an alternative embodiment example of an aeration device 51 in cross section.
  • the aeration device 51 comprises an essentially gas-impermeable lower side 52 and a gas permeamble upper side 53 and is formed as a plastic hollow profile.
  • a middle web 54 serves for increasing the stability.
  • the ratio between height h and width b is about 1:3, but may however also be larger.
  • FIG. 3 shows the profile of an aeration device 1 according to the invention in cross section.
  • the aeration device 1 consists of an essentially T-shaped carrier 2 and of a membrane 6 attached on the upper side 4 of the carrier 2 .
  • fastening means 15 which are designed in the form of a tube 19 .
  • the membrane 6 along the longitudinal sides 4 is connected to the carrier 2 .
  • the membrane 6 is formed in two parts and along a middle line 8 which runs parallel to the longitudinal sides 4 is connected to the carrier 2 .
  • the formation of two air chambers 7 a , 7 b leads to a symmetric design and avoids coalescence (unification of bubbles).
  • the fastening means 15 are provided with a cavity 18 which serves for accommodating a ballasting medium M.
  • the ballasting medium M serves for compensating the thrust of the air chambers 7 a , 7 b between the carrier 2 and the membrane 6 in water.
  • FIG. 4 shows schematically a retaining device 16 in which an aeration device 1 according to the invention is retained.
  • the retaining device is designed adjustable in height which permits a simple levelling of the aeration device.
  • the aeration device along a circumferential section 20 of the tube 19 (see FIG. 3) is snapped into a receiver opening 21 of the retaining device 16 .
  • Introduction aids 22 are provided, these simplifying the insertion of the aeration device 1 into retaining device 16 .
  • FIG. 4 there is represented a lifting device 31 by way of which the fastening device is gripped from below, snapped out of the retaining device 16 and lifted from the clearing basin.
  • FIG. 5 shows schematically an aeration device 1 according to the invention which is assembled on two retaining devices 16 .
  • the aeration device 1 comprises two air chambers 7 a and 7 b .
  • the air chambers are on the one side closed by an end piece 13 and on the other side by an air connection 10 and via a flexible connection conduit 12 connected to an air supply. Thanks to this design the aeration device 1 may be manufactured as an extrusion profile in any length.
  • the air supply is effected on the end face of the aeration device 1 .
  • FIG. 6 there is provided a device for draining the air chambers 7 a and 7 b .
  • a downwardly aligned opening may be provided which is closed with a tension rubber 27 .
  • a ball 26 which is lighter than water is placed from the inner side of the end piece 13 into the opening 28 .
  • the ball is lifted, and the water may exit downwards through the opening 28 .
  • the air supply is again turned on, the water is pressed out through the opening.
  • the ball 26 sinks again onto the opening 28 and the opening 28 is closed.
  • the floor 29 of the draining means 25 is advantageously arranged deeper than the surface 3 of the carrier 2 , so that any occuring water entering into the air chambers 7 a automatically flows into the draining means 25 .
  • the carrier 2 is preferably manufactured from polypropylene.
  • the membrane may be manufactured from a thermoplastic elastomer such as for example Santoprene.
  • the individual modules of the aeration device 1 comprise typically a length of 1 to 8 meters.
  • the thickness of the membrane 6 is between 1 and 3 mm, the thickness of the carrier 2 approx. 4 to 6 mm.
  • the air chambers are in each case approx 50 to 150 mm wide, which leads to a total width with two air chambers 7 a , 7 b of 10 to 300 mm.
  • As a ballasting medium M preferably sand is used. However other materials such as gravel, stone, concrete, etc. are conceivable.

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  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Microbiology (AREA)
  • Aeration Devices For Treatment Of Activated Polluted Sludge (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
US09/261,493 1998-03-03 1999-03-03 Aeration device for water and a method for manufacturing an aeration device Abandoned US20020003314A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP98103729.4 1998-03-03
EP19980103729 EP0947471A1 (fr) 1998-03-03 1998-03-03 Dispositif pour l'aération de l'eau et procédé de fabrication d'un aérateur

Publications (1)

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US20020003314A1 true US20020003314A1 (en) 2002-01-10

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EP (1) EP0947471A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040124550A1 (en) * 2002-08-13 2004-07-01 Itt Manufacturing Enterprises, Inc. Strip diffuser
EP2018905A1 (fr) 2007-06-11 2009-01-28 ITT Manufacturing Enterprises, Inc. Diffuseur à bandes
US8371561B2 (en) 2010-04-12 2013-02-12 Xylem Ip Holdings Llc Aeration diffuser assembly end seal
US20150001744A1 (en) * 2013-07-01 2015-01-01 NORRES Beteiligungs-GmbH Device for Distributing Gases in Liquids
US20220347636A1 (en) * 2019-09-25 2022-11-03 Sanki Engineering Co., Ltd. Air diffuser

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102008029273B4 (de) * 2008-06-19 2012-12-20 Stephan Schmidt-Holthausen Vorrichtung zum Begasen einer Flüssigkeit, insbesondere zum Belüften von Abwasser, sowie Klärbecken

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2261994A1 (de) * 1972-12-19 1974-06-20 Martin Dipl-Ing Danjes Einrichtung zum feinblasigen belueften von abwasser
DE8706219U1 (de) * 1987-04-30 1988-09-01 Tiefel, Johann, 86316 Friedberg Belüfter zum Anreichern einer Flüssigkeit mit Gas
DE4206136A1 (de) * 1991-03-02 1992-09-03 Herbert Nemetz Beluefter
EP0806400A1 (fr) * 1996-05-07 1997-11-12 Reinhart Dr.-Ing. Von Nordenskjöld Aérateur courbé

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040124550A1 (en) * 2002-08-13 2004-07-01 Itt Manufacturing Enterprises, Inc. Strip diffuser
EP1545753A1 (fr) * 2002-08-13 2005-06-29 Itt Manufacturing Enterprises, Inc. Diffuseur a bandes pct i
EP1545753A4 (fr) * 2002-08-13 2007-03-07 Itt Mfg Enterprises Inc Diffuseur a bandes pct i
US7255333B2 (en) * 2002-08-13 2007-08-14 Itt Manufacturing Enterprises, Inc. Strip diffuser
EP2110170A2 (fr) 2002-08-13 2009-10-21 ITT Manufacturing Enterprises Inc. Diffuseur de bande à membrane pour traitement des eaux usées
EP2110170A3 (fr) * 2002-08-13 2009-12-09 ITT Manufacturing Enterprises Inc. Diffuseur de bande à membrane pour traitement des eaux usées
US8002249B2 (en) 2002-08-13 2011-08-23 Itt Manufacturing Enterprises, Inc. Strip diffuser
EP2018905A1 (fr) 2007-06-11 2009-01-28 ITT Manufacturing Enterprises, Inc. Diffuseur à bandes
US8371561B2 (en) 2010-04-12 2013-02-12 Xylem Ip Holdings Llc Aeration diffuser assembly end seal
US20150001744A1 (en) * 2013-07-01 2015-01-01 NORRES Beteiligungs-GmbH Device for Distributing Gases in Liquids
US9512020B2 (en) * 2013-07-01 2016-12-06 NORRES Beteiligungs-GmbH Device for distributing gases in liquids
US20220347636A1 (en) * 2019-09-25 2022-11-03 Sanki Engineering Co., Ltd. Air diffuser

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AS Assignment

Owner name: HUBER + SUHNER AG, SWITZERLAND

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CANTZ, THOMAS;REEL/FRAME:009979/0251

Effective date: 19990309

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION